1. Field of the Invention
The present invention relates to a data driving Integrated Circuit (IC), a light emitting display using the IC, and a method of driving the light emitting display, and more particularly, to a data driving IC to display an image with a desired brightness, a light emitting display using the IC, and a method of driving the light emitting display.
2. Related Art
Various flat panel displays have recently been developed as alternatives to a relatively heavy and bulky cathode ray tube (CRT) display. The flat panel display includes a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), a light emitting display (OLED), etc.
Among the flat panel displays, the light emitting display can emit light for itself by electron-hole recombination. Such a light emitting display has advantages in that response time is relatively fast and power consumption is relatively low. Generally, the light emitting display employs a transistor provided in each pixel for supplying current corresponding to a data signal to a light emitting device, thereby allowing the light emitting device to emit light.
A light emitting display includes: a pixel portion having a plurality of pixels formed in a region defined by the intersections of scan lines and data lines; a scan driver to drive the scan lines; a data driver to drive the data lines; and a timing controller to control the scan driver and the data driver.
The timing controller generates a Data Control Signal (DCS) and a Scan Control Signal (SCS) corresponding to an external synchronization signal. The DCS and the SCS are supplied from the timing controller to the data driver and the scan driver, respectively. Furthermore, the timing controller supplies external data to the data driver.
The scan driver receives the scan control signal SCS from the timing controller. The scan driver generates scan signals on the basis of the scan control signal SCS and supplies the scan signals to the scan lines.
The data driver receives the DCS from the timing controller. The data driver generates data signals on the basis of the DCS and supplies the data signals to the data lines while synchronizing with the scan signals.
The display portion receives a first voltage ELVDD and a second voltage ELVSS from an external power source, and supplies them to the respective pixels. When the first voltage ELVDD and the second voltage ELVSS are supplied to the pixels, each pixel controls a current corresponding to the data signal to flow from a first voltage ELVDD to a second voltage ELVSS via the light emitting device, thereby emitting light corresponding to the data signal.
That is, in such a light emitting display, each pixel emits light with predetermined brightness corresponding to the data signal, but cannot emit light with desired brightness because transistors provided in the respective pixels are different in threshold voltage from each other. Furthermore, in such a light emitting display, there is no method of measuring and controlling a real current flowing in each pixel in correspondence with the data signal.